Improvement in hoisting apparatus



I UNITED STATES PATENT OFFICE.

To all Be it known that I, WALTER of New York,-have invented certain new an 1m prove hereby connection with the accom forms such a full, clear, of the same as will enable others skilled in the art My invention has for its object the economical applicati wise ordinary available power, derive mover,

consequently exp In most storelike buildings chandise or other veyed to or from the upper stories by means of an elevator consisting o lass, around which is woun attached to the platform. the drum is mounted the in the crease or groove of which is passed an endless cord of such len different stories of th cord is pulled, the wheel is rotated, which causes rope or cable and thus to to any tion of former weights 0 is necessarily cons travel of the ammals.

the ap method of operating th the improvement su be mor In the accompanying a side elevation, and F g. of an elevator construct my inv tion of In the said figures th m-and other acc platfor appara WALT-En K. MARVIN,

on NEW YORK, N. Y.

Specification forming part of Letters P whom itmay concern:

K. MARVIN, and State of New d useful ments in Hoisting Apparatus; and I t the following, taken in pan'ying drawings, (1 exact description York, in the county declare tha to make and use the same.

on to hoisting apparatus, of other or suitable construction, of d from some prime thereby to save labor and time, and

ense.

houses, factories, and other of two or more stories merarticles are generally -conf a drum or windd the rope or cable Upon'the shaft of wheel, so called,

gth as to traverse the. e building. When the the Windlass or drum to wind upthe elevate the platform Such is the hoisting used in most of our any mode of op directapplicathe force of men or animals. In the instance, but comparatively small an be raised; in the latter much time umed by the back and forth Fromthis outline of paratus heretofore used, and of its e same, the nature of bject of this patent will tood and appreciated. drawings, Figure 1 is 2 asectional View, ed in accordance wit a detail view in sechereinafter referreddes'ired height.

Now, the ordin e readily unders ention. Fig. 3 is one of the pulleys,

e drum or windlass and essories of the hoisting f the wheel, are

tus, with the exception 0 swinging upon a "nnlar mold is then app atent No. 46,957, dated February 7, 1865.

omitted, as my improvement is adaptable to any hoisting apparatus in use.

The wheel W is in a frame, A, and is confine the endless rope here shown grooved to It. At some distance below the wheel, (it is immaterial where located, provided it be within the space of the pendent portion of the rope,) there is a fixed pulley, 1?, preferably of a diameter equal to that of the wheel or pulley W, and opposite this fixed pulley, and in the plane thereof, there isa movable pulley, P--t-hat is, a pulley whose bearings a are arranged within a beam, B, fixed point of suspension, I).

Thisbeam may be made of two branches, or

it may be slotted to contain the pulley P.

s P and P, which are made of cast-iron, are shown to be of semi- The grooves of. the pulley circular section, but I prefer to make them shallower, so that the rope may not be wholly inclosed and liable to be compressed when the fixed and loose pulley are'bro'ught together.

In order to increase the frictional hold of the pulleys P and P upon the rope, I form a lining of the groove of vulcanized india-rubher, which I have found can be made to permanently adhere to the surface of the groove by vulcanizing the same upon the pulleys. To this effect the lining is formed of a proper vulcanizable compound, which is put in a plasticstate in the groove of the pulley. An anof the pulley, closed, and put into the heater to be vulcanized. To facilitate the operation of the swinging beam, I use an eccentric, S, to which may be attached a lever or handwheel, so that by lifting or depressing the lever or by rotating the hand-wheel the eccentric is caused to move the beam which brin gs the pulleys I and P into frictional contact with the rope. With the fixed pulley is geared or otherwise connected the prime mover, so that rotary. motion may be imparted to it at pleasure. It'there be a steam-engine in the vicinity, steam-power can be advanta geously employed to drive the pulley P; if not, any other available power can be used, or a horse-power can be specially used for supplyin g the power to the hoisting apparatus.

The operation is as follows: The pulley P, being supposed driven by some motive power,

hung in suitable bearings lied to the peripheryit will be understood it will freely revolve between. the pendentrope without imparting any motion thereto; but when it is desired to lift a weight or platform, then it is only necessary to pinch the rope, by bringing the pul- 1e P intofrictional contact with the rope and pulley P, the force of compression being regulated according to the weight to be raised.

This arrangement thus afl'ords themeans of working the apparatus without a brake, as the speed and power can be easily controlled by slackening or increasing the-pressure of one pulley against the-other.

A modified form of this apparatus issnown drawings, or in anyother manner which is.

equivalently the same: A fourth grooved pulley, F, secured in the end of a swinging lever, L, is used to take up the slack of and to produce tension upon the rope and to bind thepulleys, so as to cause their moving in unison,if either be driven. Themovement of a steam-engine or other prime mover may be transmitted by belting to the pulleys P P P, the second of which is fast while the other two are loose on the shaft of the grooved pul- It will be understood that the operation of this machine is like the one before described, the pulleys being brought into frictional relation by pressing on the lever L with a force proportionate to the weight to belifted.

Having thus described my invention, and the manner in which the same is or may be carried into efl'ect, I claim--.

The method herein described of applying power to hoisting apparatus by the employment of friction-pulleys operating by compression upon a rope or cable, or the equivalent therefor, substantially in the manner herein set forth.

In testimony whereof I have signed. my name to this specification before two subscribing witnesses.

, WALTER K. MARVIN.

Witnesses:

. H. W. BOOKSTANE,

ISAAC JELFS. 

